Baker&#39;s oven.



F. KfiHTz.

BAKER'S OVEN.

APPLICATION IILED MAR. 2, 1912.

1,029,134, Patented June 11,1912.

3 Fig.1

A /M; ammwa 7 COLUMBIA PLANOURAPH C0,. WASHINGTON, D. c.

rninnnrcn Knrrrz', or CANNSTATT-ISTUTTGART, GERMANY.

BAKERS OVEN.-

, Specification of Letters Patent.

Patented June 11, 1912.

Application filed March 2, 1912. seven No. 681,193.

To all whom it may concern:

Be it known that I, FRIEDRICH Kt'uirz, a subject of the King of Prussia,German Emperor, residing at Cannstatt-Stuttgart, in the Empire ofGermany, have invented a new and useful Bakers Oven, of which thefollowing is a specification.

My invention relates to bakers ovens with portable hearth adapted toopen and to close a trap-door on being pushed in and consists in amechanism operated by the hearth for again opening the trap-door andkeeping the same in the open state on the hearth being withdrawn.

I will now proceed to describe my invention with reference to theaccompanying drawing, in which Figure 1 is a vertical longitudinalsection through the baking chamber of a bakers oven and shows thetrap-door in its closed state and the portable hearth pushed in. Fig. 2is the left part of this chamber and shows the trap-door in its openstate and the rear part of the portable hearth beneath the door. Fig. 8is a vertical cross section through a part of the baking chamber and arear view of the portable hearth and the open trap-door, parts beingshown in section, and Fig. 4 is ahorizontal section through this part ofthe baking chamber and a plan view of the parts shown in Fig. 2, a partof the trapdoor being broken away.

Similar characters of reference refer to similar parts throughout theseveral views.

11 denotes a rectangular baking chamber of a bakers oven of any approvedconstruction (not shown). A trap-door 1 is at the ends rigidly connectedwith two pivots 2 which are mounted to turn in a furnace front 12 andcarry without weighted arms 3 for partly balancing the trap-door. Theweighted arms 3 are so disposed as to normally press the trap-door 1against the inner edge of the opening 18, as is clearly shown in Fig. 1.The furnace front 12 is assumed to be provided with apertures in whichtwo parallel movable rails 8 of a U shaped cross section are guided. Thefront ends of the two movable rails 8 may be connected together bymeansof a bent handle 14: so to form a frame which can be pushed inward anddrawn outward by means of the handle. The rear ends of the two movablerails 8 are shown to be provided with a long slot 15 in which the endsof a shaft 16 engage. On this shaft 16 are fastened two wheels 17, whichare adapted to roll on two parallel rails 18 (Fig. 23) secured in thebottom of the chamber 11. It is to be noted, that during thelongitudinal motion of the rails 8 the outer ends of the shaft 16 are toroll on the upper inside of the two slots 15, so as to render everylubrication unnecessary. On account of the ratio between the wheel 17and the shaft 16 the travel of the wheel is much longer than the lengthof the slot 15. Each rail 8 is on its upper surface provided with ledges19, 19 forming races for two balls 20, 20. On these balls a rectangularhearth or pan 7 is made to roll, it being provided on its lower sidewith ledges 21, 21 forming races in which the balls engage. The rearborder of the hearth 7 is provided with a known inclined arm 9 carryinga roller 10, which latter is adapted to hold the trap-door 1 in itsopened state, as is clearly shown in Figs. 2 and 3. On either side wallof the baking chamber 11 is fastened a suitable support 22 (Fig. 1) fora pin 23, on which pin a cam 6 is mounted to rock. The trap door 1 is oneither side rigidly connected with an arm 4, which projects inward andis pivotally connected with the cam 6 by means of a rod 5. Suitablerecesses 24 may be provided at the front in the top of the chamber 11for p er mitting the arms 4 and the rods 5 to move. The cam or cams 6are adapted to ride over the side borders of the hearth 7 (Fig. '2). Thefront ends of these side borders and the lower ends of the cams 6 arerounded, as is clearly shown at Fig. 1.

The mechanism described operates as fol lows: After the hearth or pan 7has been charged with fresh wares without the oven, the hearth is pushedinward in the direction of the dotted arrow 6 in Fig. 1, so that itsrear border strikes the door 1 (as is indicated'by the dotted lines inFig. 1) and partly opens it, whereupon the door sliding first over theinclined arm 9 and afterward over the roller 10 is completely opened andkept in this position (Fig. 2). It will be seen, that the trap-door 1has by the parts 4: and (3 raised the cam or cams 6, so that the rearborder of the hearth 7 can readily engage first beneath the rounded endsand afterward beneath the straight edges of the cams 6. Then the handle14 is pushed toward the oven, so that the rails 8 supported by thewheels 17 move inward and when the balls 20, 20 strike the front ends oftheir races on the rails, the hearth 7 will be taken along with therails by the balls. As long as the cams 6 ride over the horizontal edgesof the side borders of the hearth 7 the door 1 will be prevented fromclosing. Then the frame 14:, 8 has been fully pushed inward, thetrap-door 1 still remains open, since the front end of the hearth isstill beneath it. It will be then necessary to temporarily press withthe hand on the weighted arm 3 for holding the door 1 in its open stateand to push the hearth 7 further inward, whereby the cams 6 arereleased, so that the arm 3 can be turned toward the oven for closingthe door 1. After the wares have been exposed to the heat for asufficient time, the handle 14; is seized and drawn out in the directionof the arrow (4 in Fig. 1, so that the rounded front ends of the sideborders of the hearth 7 strike the cam or cams'6 and raise them foropening the door 1, whereupon the roller 10 on the inclined arm 9 canfreely move under the door 1 (Fig. 2)

The mechanism described can be varied in many respects without departingfrom the spirit of my invention. On the drawing the trap-door 1 is shownto open inward,

Where so preferred, the door may be made to open outward, in which casethe mechanism requires to be slightly modified, the arm 4: being placedon the left side of the pins 2 in Fig. 1 andthe rod 5 being suitablylengthened or the pin or pins 23 being shifted to the front, while theweighted arm or arms 3 are of course placed on the left side of the pins2 in Fig. 1.

Evidently springs, buffers or the like may be provided where necessaryfor softening any blow during the opening or closing of the trap-door.

\Vhere so preferred, the arm 1 may be replaced by a toothed segment andthe rod 5 may be replaced by a second toothed segment meshing with thefirst segment and rigidly connected with the cam 6.

I claim: 7

1. In a bakers oven, the combination with a movable pan adapted to bepushed into the baking chamber and to be withdrawn therefrom, of atrap-door adapted to open and to close the baking chamber, a cam adaptedto rock in the baking chamber and to be raised by said pan during thewithdrawal, and means for so connecting said cam with said door as tocause both of them to simultaneously move.

2. In a bakers oven, the combination with a trap-door adapted to openand to close the baking chamber, of a pan adapted to be pushed into thebaking chamber and to be withdrawn therefrom, means on said pan foropening said trap-door on the pan being pushed in, a cam adapted to rockin the baking chamber and to be raised by said pan during thewithdrawal, and means for so connecting said cam with said door as tocause both of them to simultaneously move.

3. In a bakers oven, the combination with a furnace front, of atrap-door mounted in said furnace front to rock about an upper axis foropening and closing the baking chamber, a cam adapted to rock in thebaking chamber, means for so connecting said cam with said trap-door asto cause both of them to simultaneously move, a pan adapted to be pushedinto the baking chamber under said cam when raised and to engage behindsaid cam when lowered, and an arm with a roller at the rear end of saidpan adapted to strike and to open said trap-door, said cam being adaptedto be raised by said pan during the withdrawal.

4. In a bakers oven, the combination with a furnace front, of atrap-door mounted in said furnace front to rock about an upper axis foropening and closing the baking chamber, a supporting frame comprisingtwo parallel rails guided in said furnace front at right angles theretoand a handle connecting the front ends of the rails, said parallel railshaving each at the rear end a longitudinal slot and on the top twolongitudinal recesses, a cross shaft engaging in the longitudinal slotsof said two rails, two wheels on said shaft adapted to roll on thebottom of the baking chamber, four balls adapted to roll in thelongitudinal recesses of said two rails, a pan adapted to roll on saidfour balls and to be pushed into the baking chamber and to be withdrawntherefrom, an arm with roller at the rear end of said pan adapted tostrike and to open said trap-door, a cam adapted to rock in the bakingchamber and to be raised by said pan during the withdrawal and to dropbehind the pan at the end of the inward motion, an arm'on saidtrap-door, and a rod pivotally connecting said cam with said arm wherebysaid trap-door and said cam are caused to simultaneously move.

FRIEDRICH KUHTZ. Witnesses:

VVOLDEMAR HAUPT, HENRY HASPER.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents, Washington, D. G.

